论文部分内容阅读
目的:探讨睾酮(T)对离体3T3-L1脂肪细胞胰岛素(Ins)信号通路影响的分子机制。方法:将3T3-L1前脂肪细胞诱导成熟,用10-5 mol/L T处理12 h,免疫印迹检测细胞Ins受体底物-1(IRS-1)的酪氨酸磷酸化水平及其总蛋白IRS-1、葡萄糖转运蛋白-4(GLUT-4)的表达,以及Ins刺激下膜蛋白GLUT-4的表达。加入核因子-κB(NF-κB)或ERK1/2的抑制剂预处理,再用免疫印迹检测细胞总蛋白中IRS-1的酪氨酸磷酸化水平及其总蛋白IRS-1、GLUT-4的表达,以及Ins刺激下膜蛋白GLUT-4的表达,[3H]-2-脱氧葡萄糖([3H]-2-DG)掺入法检测葡萄糖摄取率。结果:10-5 mol/L睾酮处理12 h与非T处理组相比,细胞总蛋白IRS-1及GLUT-4的表达均增多(P<0.05),但使Ins刺激下的IRS-1的酪氨酸磷酸化水平及膜蛋白GLUT-4的表达减少(P<0.05),加入ERK1/2或NF-κB的抑制剂后,IRS-1的酪氨酸磷酸化水平及膜蛋白GLUT-4的表达、葡萄糖摄取率能部分逆转。结论:ERK1/2/NF-κB信号通路是睾酮引起胰岛素抵抗(IR)的途径之一。
AIM: To investigate the molecular mechanism of testosterone (T) effects on insulin signaling in isolated 3T3-L1 adipocytes. Methods: The 3T3-L1 preadipocytes were induced to mature and treated with 10-5 mol / L for 12 h. The tyrosine phosphorylation of Ins receptor substrate-1 (IRS-1) and its total protein IRS-1, glucose transporter-4 (GLUT-4) expression, and the expression of membrane protein GLUT-4 under Ins stimulation. Pretreatment with inhibitors of nuclear factor-κB (NF-κB) or ERK1 / 2 followed by Western blot analysis of tyrosine phosphorylation of IRS-1 and total protein IRS-1, GLUT-4 , And the expression of GLUT-4, a protein stimulated by Ins, and glucose uptake by [3H] -2-deoxyglucose ([3H] -2-DG). Results: Compared with the non-T treatment group, the expression of total protein IRS-1 and GLUT-4 increased at 10-5 mol / L testosterone for 12 h (P <0.05) The level of tyrosine phosphorylation and the expression of membrane protein GLUT-4 decreased (P <0.05). After addition of inhibitors of ERK1 / 2 or NF-κB, tyrosine phosphorylation of IRS-1 and membrane protein GLUT-4 The glucose uptake rate can be partially reversed. Conclusion: ERK1 / 2 / NF-κB signaling pathway is one of the pathways by which testosterone causes insulin resistance (IR).